1. Field of the Invention
The present invention relates to a receiving apparatus, a receiving method, a transmission system and a transmission method which communicate by transmitting multiplexed digital signals of varying types.
2. Description of the Related Art
In the conventional art, there is available an apparatus which employs analog communications, such as an analog-type mobile telephone, to transmit signals of two or more varieties, such as a voice signal and electrocardiogram data. The apparatus transmits each signal by dividing the transmission band, while the receiving side employs an analog filter or the like to sort out each signal.
However, the analog filter cannot completely separate each signal, so that it may occur that one signal is included in other signal. Additionally, the analog communication system is susceptible to noises which are included on the transmission line or transmission channel, so that it becomes difficult to provide steady communications. On the other hands a digital communication system, such as a portable telephone, a land-based mobile radiotelephone (i.e., cellular system), or the like is able to transmit only one type of signal per channel. Therefore, in the case of a the digital communication system, it is necessary to provide a mobile apparatus for each type of signals in the case where two or more signals are transmitted at the same time. Accordingly, this requires that a plurality of mobile apparatuses be operated simultaneously.
It is accordingly a primary object of the present invention to provide a receiving apparatus, a receiving method, a transmission system and a transmission method that are able to resolve the aforementioned problems.
In an aspect of the present invention, there is provided a receiving apparatus which receives a signal from a communications network, said receiving apparatus consists of,
a receiving means for receiving said signal from said communications network,
an error control code type judgment means for judging the type of error control code which is added to said signal, and
a first signal type judgment means for judging tile type of said signal on tie basis of said error control code.
Furthermore, in an aspect of the present invention, there is provided a receiving apparatus, wherein said receiving apparatus further consists of a second signal type judgment means for judging the type of each signal subsequently received from said communications network on the basis of the receiving timing, which is determined by a receiving timing of said signal in which the type is judged by said first signal type judgment means, of each signal subsequently received.
Furthermore, in an aspect of the present invention, there is provided a data communication system which transmits the various types of signals from a transmission apparatus to a receiving apparatus, wherein said transmission apparatus further consists of;
an adding means for adding an error control code to each of said various types of signals according to the signal type, and
a first transmission means for transmitting said various types of signals in which said error control code is added,
wherein said receiving apparatus further consists of,
a receiving means for receiving said various types of signals, and
a first signal type judgment means for judging the type of each of said various types of signals according to the error control code which is added to each of said various types of signals.
Furthermore, in an aspect of the present invention, there is provided a data communication system, wherein said transmission apparatus further consists of a second transmission means for transmitting said various types of signals at predetermined timing, and
said receiving apparatus further consists of a second signal type judgment means for judging the type of each signal subsequently received from said communications network on the basis of the receiving timing, which is determined by a receiving timing of said signal in which the type is judged by said first signal type judgment means, of each signal subsequently received.
Furthermore, in an aspect of the present invention, there is provided a data receiving method comprising:
a step for receiving signals from communications network,
a step for judging the type of an error control code which is added to said signals, and
a step for judging the type of each of said signals on the basis of the type of said error control code.
Furthermore, in an aspect of the present invention, there is provided a data receiving method, additionally having a step for judging the type of each signal subsequently received from said communications network on tile basis of the receiving timing of said subsequently received signal.
Furthermore, in an aspect of the present invention, there is provided a data communication method which transmits the various types of signals from a transmission apparatus to a receiving apparatus, wherein said transmission apparatus further has a step for adding an error control code to each of the various types of signals according to the signal type,
a step for transmitting the various types of signals in which said error control code is added, and
wherein said receiving apparatus further has a judgment step for judging the type of each signal according to the error control code which is added to each of the various types of signals.
Furthermore, in an aspect of the present invention, there is provided a data communication method, wherein said transmission apparatus further has a step for transmitting said various types of signals at predetermined timing, and
said receiving apparatus further has a step for judging the type of each signal subsequently received from said communications network, on the basis of the receiving timing, which is determined by a receiving timing of said signal in which the type is judged by said judgment step, of said subsequently received signal.
Therefore, in a receiving apparatus, a receiving method, a transmission system and a transmission method, it is possible to judge the type of the received signal based on the error detecting code which is added the received signal. Thus, it is possible to multiplex signals of a plurality of types using a simple digital line or digital channel.